<?php

/* HTTPBase.php
 *
 * Copyright (C) 2008 MaxMind, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

class HTTPBase{
  var $server;
  var $numservers;
  var $url;
  var $queries;
  var $allowed_fields;
  var $num_allowed_fields;
  var $outputstr;
  var $isSecure;
  var $timeout;
  var $debug;
  var $check_field;
  var $wsIpaddrRefreshTimeout;
  var $wsIpaddrCacheFile;
  var $useDNS;
  var $ipstr;
  function HTTPBase() {
    $this->isSecure = 0;
    $this->debug = 0;
    $this->timeout = 0;
    $this->check_field = "score";
    $this->wsIpaddrRefreshTimeout = 18000;
    $this->wsIpaddrCacheFile = $this->_getTempDir()."/maxmind.ws.cache";
    if ($this->debug == 1) {
      print "wsIpaddrRefreshTimeout: " . $this->wsIpaddrRefreshTimeout . "\n";
      print "wsIpaddrCacheFile: " . $this->wsIpaddrCacheFile . "\n";
      print "useDNS: " . $this->useDNS . "\n";
    }
  }

  // this function sets the checked field
  function set_check_field($f) {
    $check_field = $f;
  }

  // this function sets the allowed fields
  function set_allowed_fields($i) {
    $this->allowed_fields = $i;
    $this->num_allowed_fields = count($i);
  }

  //this function queries the servers
  function query() {
    //query every server in the list
    if (!$this->useDNS){
      $ipstr = $this->readIpAddressFromCache();
      if ($this->debug == 1){
        print "using ip addresses, IPs are " . $ipstr . "\n";
      }
    }
    // query every server using its ip address
    // if there was success reading the ip addresses
    // from the web or the cache file
    if ($ipstr) {
      $ipaddr = explode(";",$ipstr);
      $numipaddr = count($ipaddr);
      for ($i = 0;$i < $numipaddr;$i++){
        $result = $this->querySingleServer($ipaddr[$i]);
        if ($this->debug == 1) {
	  print "ip address: " . $ipaddr[$i] . "\n";
	  print "result: " . $result . "\n";
	}
        if ($result) {
	  return $result;
	}
      }
    }
    
    // query every server using its domain name
    for ($i = 0; $i < $this->numservers; $i++ ) {
      $result = $this->querySingleServer($this->server[$i]);
      if ($this->debug == 1) {
        print "server: " . $this->server[$i] . "\nresult: " . $result . "\n";
      }
      if ($result) {
        return $result;
      }
    }
    return 0;
  }

  // this function takes a input hash and stores it in the hash named queries
  function input($vars) {
    $numinputkeys = count($vars);  // get the number of keys in the input hash
    $inputkeys = array_keys($vars);   // get a array of keys in the input hash
    for ($i = 0; $i < $numinputkeys; $i++) {
      $key = $inputkeys[$i];
      if ($this->allowed_fields[$key] == 1) {
        //if key is a allowed field then store it in 
        //the hash named queries
        $this->queries[$key] = urlencode($this->filter_field($key, $vars[$key]));
      } else {
        print "invalid input $key - perhaps misspelled field?";
	return 0;
      }
    }
    $this->queries["clientAPI"] = $this->API_VERSION;
  }

  //sub-class should override this if it needs to filter inputs
  function filter_field($key, $value) {
    return $value;
  }

  //this function returns the output from the server
  function output() {
    return $this->outputstr; 
  }

  // write the ip Addresses and the time right now to
  // the cache file
  function writeIpAddressToCache($filename,$ipstr) {
    $datetime = time();
    $fh = fopen($this->wsIpaddrCacheFile,'w');
    fwrite($fh,$ipstr . "\n");
    fwrite($fh,$datetime . "\n");
    fclose($fh);
    if ($this->debug == 1) {
      print "writing ip address to cache\n";
      print "ip str: " . $ipstr . "\n";
      print "date time: " . $datetime . "\n";
    }
  }
      
  function readIpAddressFromCache() {
    // if the cache file exists then
    // read the ip addresses and the time
    // IPs were cached
    if (file_exists($this->wsIpaddrCacheFile)) {
      $fh = fopen($this->wsIpaddrCacheFile,'r');
      $ipstr = fgets($fh,1024);
      $ipstr = rtrim($ipstr);
      $datetime  = fgets($fh,1024);
      $datetime = rtrim($datetime);
      fclose($fh);
    }
     
    // if the ip addresses expired or don't exist then
    // get them from the web and write 
    // them to the cache file
    if (((time() - $datetime) > $this->wsIpaddrRefreshTimeout) | (!$ipstr)) {
      $tryIpstr = $this->readIpAddressFromWeb();
      if ($tryIpstr) {
        $ipstr = $tryIpstr;
      } else {
	if ($this->debug == 1){
	  print "Warning, unable to get ws_ipaddr from www.maxmind.com\n";
        }
      }
      // we write to cache whether or not we were able to get $tryIpStr, since
      // in case DNS goes down, we don't want to check app/ws_ipaddr over and over
      $this->writeIpAddressToCache($this->wsIpaddrCacheFile,$ipstr);
    }
    if ($this->debug == 1){
      print "reading ip address from cache\n";
      print "ip str: " . $ipstr . "\n";
      print "date time: " . $datetime . "\n";
    }
    //return the ip addresses
    return $ipstr;     
  }

  function readIpAddressFromWeb() {
    //check if the curl module exists
    $url = "http://www.maxmind.com/app/ws_ipaddr";
    if (extension_loaded('curl')) {
      // open curl
      $ch = curl_init();

      // set curl options
      curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
      curl_setopt($ch, CURLOPT_URL, $url);
      curl_setopt($ch, CURLOPT_TIMEOUT, $this->timeout);

      //get the content
      $content = curl_exec($ch);
      $content = rtrim($content);
      if ($this->debug == 1) {
        print "using curl\n";
      }
    } else {
      // we using HTTP without curl

      // parse the url to get
      // host, path and query
      $url3 = parse_url($url);
      $host = $url3["host"];
      $path = $url3["path"];

      // open the connection
      $fp = fsockopen ($host, 80, $errno, $errstr, $this->timeout);
      if ($fp) {
        // send the request
        fputs ($fp, "GET $path HTTP/1.0\nHost: " . $host . "\n\n");
        while (!feof($fp)) {
          $buf .= fgets($fp, 128);
        }
        $lines = preg_split("/\n/", $buf);
        // get the content
        $content = $lines[count($lines)-1];
        //close the connection
        fclose($fp);
      }
      if ($this->debug == 1) {
        print "using fsockopen\n";
      }
    }
    if ($this->debug == 1) {
      print "readIpAddressFromWeb found ip addresses: " . $content . "\n";
    }
    // TODO fix regexp so that it checks if it only has IP addresses
    if (preg_match ("/([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})/",$content)) {
      return $content;
    } 
    return "";
  }

  // this function queries a single server
  function querySingleServer($server) {
    // check if we using the Secure HTTPS proctol
    if ($this->isSecure == 1) {
      $scheme = "https://";  // Secure HTTPS proctol
    } else {
      $scheme = "http://";   // Regular HTTP proctol
    }

    // build a query string from the hash called queries
    $numquerieskeys = count($this->queries); // get the number of keys in the hash called queries
    $querieskeys = array_keys($this->queries); // get a array of keys in the hash called queries
    if ($this->debug == 1) {
      print "number of query keys " + $numquerieskeys + "\n";
    }

    $query_string = "";

    for ($i = 0; $i < $numquerieskeys; $i++) {
      //for each element in the hash called queries 
      //append the key and value of the element to the query string
      $key = $querieskeys[$i];
      $value = $this->queries[$key];
      //encode the key and value before adding it to the string
      //$key = urlencode($key);
      //$value = urlencode($value);
      if ($this->debug == 1) {
        print " query key " . $key . " query value " . $value . "\n";
      }
      $query_string = $query_string . $key . "=" . $value;
      if ($i < $numquerieskeys - 1) {
        $query_string = $query_string . "&";
      }
    }

    $content = "";

    //check if the curl module exists
    if (extension_loaded('curl')) {
      //use curl
      if ($this->debug == 1) {
        print "using curl\n";
      }

      //open curl
      $ch = curl_init();

      $url = $scheme . $server . "/" . $this->url;

      //set curl options
      if ($this->debug == 1){
        print "url " . $url . "\n";
      }
      curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
      curl_setopt($ch, CURLOPT_URL, $url);
      curl_setopt($ch, CURLOPT_TIMEOUT, $this->timeout);
      curl_setopt($ch, CURLOPT_SSL_VERIFYHOST,0);

      //this option lets you store the result in a string 
      curl_setopt($ch, CURLOPT_POST,          1);
      curl_setopt($ch, CURLOPT_POSTFIELDS,    $query_string);

      //get the content
      $content = curl_exec($ch);

      // For some reason curl_errno returns an error even when function works
      // Until we figure this out, will ignore curl errors - (not good i know)
//      $e = curl_errno($ch);//get error or sucess

//      if (($e == 1) & ($this->isSecure == 1)) {
        // HTTPS does not work print error message
//          print "error: this version of curl does not support HTTPS try build curl with SSL or specify \$ccfs->isSecure = 0\n";
//      }
//      if ($e > 0) {
        //we get a error msg print it
//        print "Received error message $e from curl: " . curl_error($ch) . "\n";
//	return 0;
//      }
      //close curl
      curl_close($ch);
    } else {
      //curl does not exist
      //use the fsockopen function, 
      //the fgets function and the fclose function
      if ($this->debug == 1) {
        print "using fsockopen for querySingleServer\n";
      }

      $url = $scheme . $server . "/" . $this->url . "?" . $query_string;
      if ($this->debug == 1) {
        print "url " . $url . " " . "\n";
      }

      //now check if we are using regular HTTP
      if ($this->isSecure == 0) {
        //we using regular HTTP

        //parse the url to get
        //host, path and query
        $url3 = parse_url($url);
        $host = $url3["host"];
        $path = $url3["path"];
	$query =  $url3["query"];

        //open the connection
        $fp = fsockopen ($host, 80, $errno, $errstr, $this->timeout);
        if ($fp) {
          //send the request
          $post = "POST $path HTTP/1.0\nHost: " . $host . "\nContent-type: application/x-www-form-urlencoded\nUser-Agent: Mozilla 4.0\nContent-length: " . strlen($query) . "\nConnection: close\n\n$query";
          fputs ($fp, $post);
          while (!feof($fp)) {
            $buf .= fgets($fp, 128);
          }
          $lines = preg_split("/\n/", $buf);
          // get the content
          $content = $lines[count($lines)-1];
          //close the connection
          fclose($fp);
        } else {
	  return 0;
	}
      } else {
        //secure HTTPS requires CURL
        print "error: you need to install curl if you want secure HTTPS or specify the variable to be $ccfs->isSecure = 0";
        return 0;
      }
    }

    if ($this->debug == 1) {
      print "content = " . $content . "\n";
    }
    // get the keys and values from
    // the string content and store them
    // the hash named outputstr

    // split content into pairs containing both 
    // the key and the value
    $keyvaluepairs = explode(";",$content);

    //get the number of key and value pairs
    $numkeyvaluepairs = count($keyvaluepairs);

    //for each pair store key and value into the
    //hash named outputstr
    $this->outputstr = array();
    for ($i = 0; $i < $numkeyvaluepairs; $i++) {
      //split the pair into a key and a value
      list($key,$value) = explode("=",$keyvaluepairs[$i]);
      if ($this->debug == 1) {
        print " output " . $key . " = " . $value . "\n";
      }
      //store the key and the value into the
      //hash named outputstr
      $this->outputstr[$key] = $value;
    }
    //check if outputstr has the score if outputstr does not have 
    //the score return 0
    if ($this->outputstr[$this->check_field] == "") {
      return 0;
    }
    //one other way to do it
    //if (!array_key_exists("score",$this->outputstr)) {
    //  return 0;
    //}
    return 1;
  }

  function _getTempDir() {
    if (ini_get('upload_tmp_dir')) {
      return ini_get('upload_tmp_dir');
    }

    if (substr(PHP_OS, 0, 3) != 'WIN') {
      return '/tmp';
    }

    if (isset($_ENV['TMP'])) {
      return $_ENV['TMP'];
    }

    if (isset($_ENV['TEMP'])) {
      return $_ENV['TEMP'];
    }

    if (is_dir('c:\\windows\\temp')) {
      return 'c:\\windows\\temp';
    }

    if (is_dir('c:\\winnt\\temp')) {
      return 'c:\\winnt\\temp';
    }

    return '.';
  }
}
?>